Olive leaves have been prized for thousands of years in Mediterranean countries where they have been used to promote health and wellness. Olive leaf extract possesses strong anti-microbial properties being toxic to viruses, bacterial, fungi, and parasites. Its anti-viral properties are particularly impressive, showing in vitro (laboratory) activity against herpes, HIV and the virus that causes the common cold. Olive leaf extract provides a boost to the body’s own immune response making it better able to fight disease and infection.